procfs_map.c revision 330897
1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1993 Jan-Simon Pendry 5 * Copyright (c) 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Jan-Simon Pendry. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)procfs_status.c 8.3 (Berkeley) 2/17/94 36 * 37 * $FreeBSD: stable/11/sys/fs/procfs/procfs_map.c 330897 2018-03-14 03:19:51Z eadler $ 38 */ 39 40#include "opt_compat.h" 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/lock.h> 45#include <sys/filedesc.h> 46#include <sys/malloc.h> 47#include <sys/mount.h> 48#include <sys/proc.h> 49#include <sys/resourcevar.h> 50#include <sys/rwlock.h> 51#include <sys/sbuf.h> 52#ifdef COMPAT_FREEBSD32 53#include <sys/sysent.h> 54#endif 55#include <sys/uio.h> 56#include <sys/vnode.h> 57 58#include <fs/pseudofs/pseudofs.h> 59#include <fs/procfs/procfs.h> 60 61#include <vm/vm.h> 62#include <vm/vm_extern.h> 63#include <vm/pmap.h> 64#include <vm/vm_map.h> 65#include <vm/vm_page.h> 66#include <vm/vm_object.h> 67 68#define MEBUFFERSIZE 256 69 70/* 71 * The map entries can *almost* be read with programs like cat. However, 72 * large maps need special programs to read. It is not easy to implement 73 * a program that can sense the required size of the buffer, and then 74 * subsequently do a read with the appropriate size. This operation cannot 75 * be atomic. The best that we can do is to allow the program to do a read 76 * with an arbitrarily large buffer, and return as much as we can. We can 77 * return an error code if the buffer is too small (EFBIG), then the program 78 * can try a bigger buffer. 79 */ 80int 81procfs_doprocmap(PFS_FILL_ARGS) 82{ 83 struct vmspace *vm; 84 vm_map_t map; 85 vm_map_entry_t entry, tmp_entry; 86 struct vnode *vp; 87 char *fullpath, *freepath, *type; 88 struct ucred *cred; 89 vm_object_t obj, tobj, lobj; 90 int error, privateresident, ref_count, resident, shadow_count, flags; 91 vm_offset_t e_start, e_end; 92 vm_eflags_t e_eflags; 93 vm_prot_t e_prot; 94 unsigned int last_timestamp; 95 bool super; 96#ifdef COMPAT_FREEBSD32 97 bool wrap32; 98#endif 99 100 PROC_LOCK(p); 101 error = p_candebug(td, p); 102 PROC_UNLOCK(p); 103 if (error) 104 return (error); 105 106 if (uio->uio_rw != UIO_READ) 107 return (EOPNOTSUPP); 108 109#ifdef COMPAT_FREEBSD32 110 wrap32 = false; 111 if (SV_CURPROC_FLAG(SV_ILP32)) { 112 if (!(SV_PROC_FLAG(p, SV_ILP32))) 113 return (EOPNOTSUPP); 114 wrap32 = true; 115 } 116#endif 117 118 vm = vmspace_acquire_ref(p); 119 if (vm == NULL) 120 return (ESRCH); 121 map = &vm->vm_map; 122 vm_map_lock_read(map); 123 for (entry = map->header.next; entry != &map->header; 124 entry = entry->next) { 125 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) 126 continue; 127 128 e_eflags = entry->eflags; 129 e_prot = entry->protection; 130 e_start = entry->start; 131 e_end = entry->end; 132 privateresident = 0; 133 resident = 0; 134 obj = entry->object.vm_object; 135 if (obj != NULL) { 136 VM_OBJECT_RLOCK(obj); 137 if (obj->shadow_count == 1) 138 privateresident = obj->resident_page_count; 139 } 140 cred = (entry->cred) ? entry->cred : (obj ? obj->cred : NULL); 141 142 for (lobj = tobj = obj; tobj != NULL; 143 tobj = tobj->backing_object) { 144 if (tobj != obj) 145 VM_OBJECT_RLOCK(tobj); 146 lobj = tobj; 147 } 148 if (obj != NULL) 149 kern_proc_vmmap_resident(map, entry, &resident, &super); 150 for (tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 151 if (tobj != obj && tobj != lobj) 152 VM_OBJECT_RUNLOCK(tobj); 153 } 154 last_timestamp = map->timestamp; 155 vm_map_unlock_read(map); 156 157 freepath = NULL; 158 fullpath = "-"; 159 if (lobj) { 160 vp = NULL; 161 switch (lobj->type) { 162 default: 163 case OBJT_DEFAULT: 164 type = "default"; 165 break; 166 case OBJT_VNODE: 167 type = "vnode"; 168 vp = lobj->handle; 169 vref(vp); 170 break; 171 case OBJT_SWAP: 172 if ((lobj->flags & OBJ_TMPFS_NODE) != 0) { 173 type = "vnode"; 174 if ((lobj->flags & OBJ_TMPFS) != 0) { 175 vp = lobj->un_pager.swp.swp_tmpfs; 176 vref(vp); 177 } 178 } else { 179 type = "swap"; 180 } 181 break; 182 case OBJT_SG: 183 case OBJT_DEVICE: 184 type = "device"; 185 break; 186 } 187 if (lobj != obj) 188 VM_OBJECT_RUNLOCK(lobj); 189 190 flags = obj->flags; 191 ref_count = obj->ref_count; 192 shadow_count = obj->shadow_count; 193 VM_OBJECT_RUNLOCK(obj); 194 if (vp != NULL) { 195 vn_fullpath(td, vp, &fullpath, &freepath); 196 vrele(vp); 197 } 198 } else { 199 type = "none"; 200 flags = 0; 201 ref_count = 0; 202 shadow_count = 0; 203 } 204 205 /* 206 * format: 207 * start, end, resident, private resident, cow, access, type, 208 * charged, charged uid. 209 */ 210 error = sbuf_printf(sb, 211 "0x%lx 0x%lx %d %d %p %s%s%s %d %d 0x%x %s %s %s %s %s %d\n", 212 (u_long)e_start, (u_long)e_end, 213 resident, privateresident, 214#ifdef COMPAT_FREEBSD32 215 wrap32 ? NULL : obj, /* Hide 64 bit value */ 216#else 217 obj, 218#endif 219 (e_prot & VM_PROT_READ)?"r":"-", 220 (e_prot & VM_PROT_WRITE)?"w":"-", 221 (e_prot & VM_PROT_EXECUTE)?"x":"-", 222 ref_count, shadow_count, flags, 223 (e_eflags & MAP_ENTRY_COW)?"COW":"NCOW", 224 (e_eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC", 225 type, fullpath, 226 cred ? "CH":"NCH", cred ? cred->cr_ruid : -1); 227 228 if (freepath != NULL) 229 free(freepath, M_TEMP); 230 vm_map_lock_read(map); 231 if (error == -1) { 232 error = 0; 233 break; 234 } 235 if (last_timestamp != map->timestamp) { 236 /* 237 * Look again for the entry because the map was 238 * modified while it was unlocked. Specifically, 239 * the entry may have been clipped, merged, or deleted. 240 */ 241 vm_map_lookup_entry(map, e_end - 1, &tmp_entry); 242 entry = tmp_entry; 243 } 244 } 245 vm_map_unlock_read(map); 246 vmspace_free(vm); 247 return (error); 248} 249